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Plot-level rapid screening for photosynthetic parameters using proximal hyperspectral imaging
Get PDFPhotosynthesis is currently measured using time-laborious and/or destructive methods which slows research and breeding efforts to identify crop germplasm with higher photosynthetic capacities. We present a plot-level screening tool for quantification of photosynthetic parameters and pigment contents that utilizes hyperspectral reflectance from sunlit leaf pixels collected from a plot (∼2 m×2 m) in c,max, R2=0.79) maximum electron transport rate in given conditions (J1800, R2=0.59), maximal light-saturated photosynthesis (Pmax, R2=0.54), chlorophyll content (R2=0.87), the Chl a/b ratio (R2=0.63), carbon content (R2=0.47), and nitrogen content (R2=0.49). Model predictions did not improve when using two cameras spanning 400-1800 nm, suggesting a robust, widely applicable and more 'cost-effective' pipeline requiring only a single VNIR camera. The analysis pipeline and methods can be used in any cropping system with modified species-specific PLSR analysis to offer a high-throughput field phenotyping screening for germplasm with improved photosynthetic performance in field trials.</p
Field cricket genome reveals the footprint of recent, abrupt adaptation in the wild
Get PDFEvolutionary adaptation is generally thought to occur through incremental mutational steps, but large mutational leaps can occur during its early stages. These are challenging to study in nature due to the difficulty of observing new genetic variants as they arise and spread, but characterizing their genomic dynamics is important for understanding factors favoring rapid adaptation. Here, we report genomic consequences of recent, adaptive song loss in a Hawaiian population of field crickets (Teleogryllus oceanicus). A discrete genetic variant, flatwing, appeared and spread approximately 15 years ago. Flatwing erases sound‐producing veins on male wings. These silent flatwing males are protected from a lethal, eavesdropping parasitoid fly. We sequenced, assembled and annotated the cricket genome, produced a linkage map, and identified a flatwing quantitative trait locus covering a large region of the X chromosome. Gene expression profiling showed that flatwing is associated with extensive genome‐wide effects on embryonic gene expression. We found that flatwing male crickets express feminized chemical pheromones. This male feminizing effect, on a different sexual signaling modality, is genetically associated with the flatwing genotype. Our findings suggest that the early stages of evolutionary adaptation to extreme pressures can be accompanied by greater genomic and phenotypic disruption than previously appreciated, and highlight how abrupt adaptation might involve suites of traits that arise through pleiotropy or genomic hitchhiking
Cría y Mejoramiento Genético Animal
No full textÍNDICE DE CAPÍTULOS (1° PARTE, CAPÍTULOS 1 A 7) • Capítulo 1: Introducción al mejoramiento genético animal • Capítulo 2: Conceptos básicos de la cría y mejoramiento de animales • Capítulo 3: Las razones para mantener a los animales determinan el objetivo de la cría y mejoramiento genético • Capítulo 4: La recopilación de información para la toma de decisiones • Capítulo 5: Los Modelos Genéticos • Capítulo 6: La diversidad genética y la endogamia • Capítulo 7: La herencia de rasgos monogénico
Veelbelovende perspectieven om fotosynthese flink omhoog te krijgen : Betere benutting van de zonnestraling onderzocht
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More frequent droughts slow down litter decomposition across European agroecosystems and increase the importance of earthworm functional diversity
No full textEffects of increasing rainfall variability and weather extremes on litter decomposition are still uncertain, especially in agroecosystems, where the functional structure of soil communities is already affected. We conducted a mesocosm experiment to evaluate the impacts of different rain regimes and land management on litter mass loss and earthworm ecological groups (epigeic, endogeic and anecic) across European agroecosystems. We also tested if the effects of different rainfall regimes (normal, drought, flooding, intermittent) on earthworm functional diversity (FD) or community-weighted mean (CWM) of earthworm ecological groups (particularly anecic species in the case of CWM), affected litter mass loss across land-use types. We found that drought was the main factor retarding litter mass loss across European agroecosystems irrespective of management type. The effects of the rain regime on litter mass loss were coupled with the pedoclimatic conditions that were different among the studied European land-use types. Across land-use types the importance of earthworm communities for litter decomposition was higher under water depletion. These results also suggest that FD, as a proxy of niche complementarity, is crucial for the stability of the decomposition process under environmental disturbances. The FD values under drought regimes strongly indicated that climatic changes may slow down litter decomposition as a result of FD alterations that could compromise the long-term maintenance of litter mass loss. This result may be especially relevant for the European soils that are already under hydric stress, such as in most Mediterranean agroecosystems.</p
Progress Report NIGI Uganda 2019 : Nutrition and Income Generation Intervention, West Nile, Uganda
Get PDFThis report can also be downloaded from: http://www.d-portal.org
Science, subsidies and the politics of the pulse trawl ban in the European Union
No full textThe decision to ban the pulse trawl by the European Parliament in early 2019 was influenced by public debate over its scientific and political legitimacy. In their 2019 paper in Marine Policy, Le Manach et al. continued this debate by making three claims. First, that the pulse trawl has substantial negative social and environmental impacts. Second, that it received ‘illegal’ subsidies from the European Union amounting to €20.8 million. And third, that the Dutch government and industry did not provide adequate transparency in the allocation of subsidies. These claims are misleading and, in some instances, demonstrably false: the ongoing science on the effects of the pulse trawl shows relatively positive impacts; following the conventional definitions of “harmful” and “fisheries subsidies” in the economic literature, harmful subsidies provided to pulse trawling only amount to €0.3 million, or less than 2% of Le Manach et al.‘s estimate; and there is no evidence of intentional non-disclosure of information related to the distribution of subsidies by the Dutch government. Finally, we reflect on the consequences of the inaccuracies presented by Le Manach et al. in the governance of fishing gear innovation and their wider effect on the legitimacy of advocacy-based science
Quality Management Practices of Gene Banks for Livestock: A Global Review
No full textThe genetic diversity of livestock is decreasing and many countries have created gene banks for ex situ–in vitro conservation of animal genetic resources (AnGR). The collection, processing, and storage of animal germplasm require substantial investment and the material collected (and associated data) is highly valuable. Therefore, quality management systems (QMSs) and practices are important. The objective of this study was to review the quality management procedures of livestock gene banks around the world to identify the general strengths and weaknesses of quality control. A survey was administered by means of an online questionnaire consisting of 54 questions, most of which were yes/no with respect to the presence of a particular aspect of quality management. The survey was distributed through networks of the Food and Agriculture Organization of the United Nations that are associated with AnGR. Ninety responses were received from 62 countries. The gene banks were predominantly public institutions, with the main goal of preventing breed extinction. Approximately 30% of the banks reported having a QMS, 15 of which involved formal certification. Many other banks have plans to implement formal quality management within the next 5 years. Regarding specific aspects of quality management, more emphasis was placed on material entering the banks than on eventual utilization. Among the banks processing and freezing material, 90% followed specific standard operating procedures, but only 24% had policies regarding provision of access to external stakeholders. Increased cooperation among livestock gene banks could improve quality management. Sharing of knowledge could standardize procedures and cooperating peers could evaluate each other's QMSs
Data from: "Microcredit to women and its contribution to production and household food security"
No full textThis data was collected as part of the PhD project for Faith Muyonga Namayengo. Respondents were BRAC microfinance clients in three districts of Uganda. The baseline data collection was in 2013 while the follow up study was in the year 2014. Data collection was funded by the NUFFIC Netherlands Fellowship Program and the SEPON Foundatio